Locking and releasing mechanism for foldable table legs



July 5, 1955 G. H. KLEINSORGE 2,712,486

LOCKING AND RELEASING MECHANISM FOR FOLDABLE TABLE LEGS Filed April 17,1953 2 Sheets-Sheet l INVENTOR. GEORGE H .KLEINSORGE AGENT July 5, 1955G. H. KLEINSORGE 2,712,436

LOCKING AND RELEASING MECHANISM FOR FOLDABLE TABLE LEGS Filed April 17,1953 2 Sheets-Sheet 2 FIG.6.

IN V EN TOR. GEORGE H. KLEINSORGE MM M AGENT United States Patent GLOCKING AYD RELEASING MECHANISM FOR FOLDABLE TABLE LEGS George H.Kleinsorge, Chicago, Ill.

Application April 17, 1953, Serial No. 349,416

2 Claims. (Cl. 311-87) This invention relates to foldable or collapsibletables and more specifically to the locking and releasing assembly ofthe supporting members of such tables.

Heretofore it has been customary to provide foldable tables withsuitable means for locking the supporting members in a relatively firmand rigid operative posi- L tion to prevent the collapse of the tablewhen in use. Associated with the locking means, was a means foreffecting the unlocking of the supporting members to fold them andpermit convenient storage of the table when not in use. The constructioncommonly adopted, however, usually required placement of the table intodifierent positions, or required awkward manipulation by the operator togain access to the locking and releasing assembly. It is, therefore, anobject of the invention to provide a new and improved folding tablehaving pairs of legs defined by U-shaped members providing forsimultaneous opening, locking and unlocking of each pair of legs.

It is a further object of the invention to provide a folding table, thelegs of which can be collapsed while the table is supported on one edgewithout it being necessary to lift the table and place it in differentpositions.

Other objects will appear hereinafter as the description of theinvention proceeds.

The novel features of the invention and how the objects are attainedwill appear from this specification and the accompanying drawing forminga part of this application.

In the drawings:

Fig. 1 is a plan view of the bottom side of the table in its fullyunfolded condition; with portions of its supporting members broken awayto clarify the construction;

Fig. 2 is a side elevation of the table according to Fig. 1 showing indot and dash lines one of the supporting members in a state of beingfolded with the front brace partly broken away;

Fig. 3 is a side elevation of the table with one of the supportingmembers in folded condition indicating in dot and dash lines the partlyfolded condition of the other supporting member;

Fig. 4 shows the locking mechanism on a larger scale, and

Fig. 5 is a side view of Fig. 4;

Fig. 6 is a plan view of the table in its folded condition showing thenarrower leg structure adjacent the springs for locking in place thewider leg structure.

The collapsible table illustrated generally comprises a flat table top 1of wood, metal or any other suitable material, supporting members 2, 3,adapted to firmly support the flat top 1 in operative condition, andlocking devices 4, 5, constructed and arranged in a novel cooperativemanner with the supporting members 2, 3, to permit locking and releasingthereof.

In accordance with the invention a collapsible table comprises a flattop, first and second U-shaped supporting members foldable toward eachother, each including at least one bracing member and a locking deviceincluding a spring and a slotted bracket secured to said flat top, saidsupporting members being pivotally supported on said slotted bracketsrelative to said flat top and said locking devices, each of said bracingmembers extending substantially parallel to the associated slottedbracket and having a pin at one end in sliding engagement with theassociated slotted bracket and having pivotal engagement at the otherend with the associated supporting member, each said spring having atransverse groove and being biased towards the pin in the associatedslotted member, said first supporting member being of less width thansaid second supporting member and one of said springs associated withthe bracing member of said second supporting member being aligned with aleg of said first supporting member when in folded condition fordisplacement thereby to release the pin in the slotted bracket of saidsecond supporting member.

The supporting members 2, 3, comprise a pair of leg frames which may betubular U-shaped structures as shown. The supporting member 2 is shownas a first U-shaped leg frame having a predetermined transverse width,and the supporting member 3 is shown as a second U-shaped leg framehaving a greater transverse width for reasons hereinafter explained. Thelocking device 4 is associated with the supporting member 2, and thelocking device 5 is associated with the supporting member 3.

Each locking device includes at least one slotted member such aselongated angular brackets 6, 7, rigidly secured to the underside of thefiat top 1 by any suitable means. The brackets 6, 7, are associated withtheir supporting members 2, 3, in such manner that they arelongitudinally parallel to each other and transversely aligned. Thebrackets are mounted so that the surfaces, secured to the fiat top 1extend inwardly or toward each other. The vertical portions 9 of thebrackets have secured thereto the terminal ends 8 of the supportingmembers 2, 3, which are pivotally joined to the inner surfaces thereofby studs 10. The vertical portions 9 are provided with longitudinallyextended slots 11.

Each supporting member 2, 3, includes a pair of bracing members shownhere as links 12. The links 12 are provided at one end with pins 13usually of circular cross section which extend transversely to the linksand slidably engage the slots 11 of the associated brackets. Theopposite ends of the links 12 are pivotally secured to the supportingmembers 2, 3, to form jack knife joints therewith and with the brackets.Substantially midway between the ends of the links 12 is an offsetportion 14 provided to clear the studs 10, when the supporting members2, 3, are folded toward each other.

As shown in the drawing, a spring 15 usually of the leaf type isincluded in each locking device. One end of the springs is fastenedapproximately centrally of the brackets. The free ends of the springsextend beyond the ends of the brackets and they are provided withgrooves 16 as may best be seen in Fig. 5. The biasing action of thesprings is outward from the flat top 1 or toward the pins. One pair ofleaf springs are here shown as interconnected by a rod 17 in any desiredmanner, so that pressure applied to the rod in the direction of the fiattop 1 disengages pins 13 from the grooves 16, thereby releasing legs 2for folding action.

The brackets associated with [J -shaped supporting member 3 are morewidely spaced than the brackets associated with U-shaped supportingmember 2, in such a manner that when the U-shaped supporting member 2 isfolded its U-shaped leg frame will readily pass between the legs definedby U-shaped member 3 and contact the springs associated with brackets 7.

The manipulation of the table to the folded condition can best bedescribed by reference to Figs. 2 and 3.

Here it is seen that the table is placed in a vertical position to restupon one end. The operator then depresses the rod 17 with one hand untilgrooves 16 of the leaf springs 15 disengage from the pins 13. Since thetable is in balanced vertical position the operators other hand is freeto swing the narrow U-shaped leg frame 2 downwardly as shown by the dotdash lines in Fig. 2. In Fig. 3 the narrow U-shaped leg frame 2 is showncompletely folded, at which time the legs of this frame are inengagement with the springs 15 associated with the wider U-shaped legframe 3.

Now in order to make it unnecessary for the operator to turn the tablearound with its other end upward for the purpose of depressing thesprings 15 associated with the locks of leg frame 3 it is possible inaccordance with the invention to rely on the proximity of the lower endsof legs 2 to the springs 15 associated with the locks of leg frame 3. InFig. 3 the leg frame 2 is shown to be pressed inwardly against springs15 to unlock locking devices 5, thereby releasing frame 3 for folding itupwardly, over and around leg frame 3.

The action of pressing the frame 2 inwardly to fold frame 3 may beeffected with the operators foot. The

operator holds the upper end of the table with the right hand, pressingframe 2 with the left foot inwardly against springs 15. therebyreleasing the pressure against pins 13. Now if the top of the table istilted to the left, the end of leg frame 3 touches the floor and furthertilting motion moves it upwardly. Frame 3 may then be seized with theleft hand and brought into folded position substantially parallel to thefiat top.

To unfold the leg frame it is necessary to first unfold the wider frame3 and then the narrower frame 2. If the embodied in other combinationsthan that illustrated,

without departing from the spirit of the invention. For example, one ofthe springs 15 could be omitted from locks 7. Accordingly the disclosureherein is illustrative only and the invention is not limited the ,to.

Having now described fully the invention what I claim l. A collapsibletable comprising a fiat top, first and second U-shaped supportingmembers foldablc toward each other, each including at least one bracingmember and a locking device including a spring and a slotted bracketsecured to said fiat top, said supporting members being pivotallysupported on said slotted brackets relative to said fiat top and saidlocking devices, each of said bracing members extending substantiallyparallel to the slotted bracket and having a pin at one end in slidingengagement with the slotted bracket and having pivotal engagement at theother endwith the supporting member, each said spring having atransverse groove and being biased towards the pin in the slottedmember, said first supporting member being of less width than saidsecond supporting member and said spring of said at least one bracingmember of said second supporting member being aligned with a leg of saidfirst supporting member when in folded condition for displacementthereby to release the pin in the slotted bracket of said secondsupporting member.

2. A collapsible table comprising a top, first and sec-1 0nd U-shapedleg structures foldable toward each other and including each at leastone bracing member and a locking device for holding the legs in unfoldedposition, said locking devices including a springand a slotted bracketsecured to said top, said leg structures being pivotally supported onsaid slotted brackets relative to said top, each of said bracing membersextending substantially parallel to its said slotted bracket and havinga pin at one end in sliding engagement with said slotted bracket andhaving at the other end pivotal engagement with the leg structure, eachsaid spring having a transverse groove for engagement by said pin andbeing biased towards said pin, the Width of said first leg structurebeing less than the width of said second leg structure and said springof said at least one bracing member of said second leg structure beingaligned with one leg of said first leg structure when said first legstructure is in folded condition for displacement thereby a manner toeffect release of the pin in the slotted bracket of said second legstructure.

References Cited in the file of this patent UNITED STATES PATENTS SwartIuly 31, 1906

